bliss



w. L. BL|SS. VARIABLE RESISTANCE REGULATOR FOR ELECTRIC CIRCUITS.

APPLICATION FILED APR. I7. I914- 1,310,599. Patented July 22, 1919.

Jig j 2 9 V j 5 g 21 (IMAM w imam-mg UNIAITED sTArEs rAT NT oFFIoE.

1.. Brass, or menu runs, n-nw Yon'x, 'n'ssrenon. To U. s. new a I narconromrron. or mom runs, NEW max, A conromnon or HEW YORK.

vmum-nnsrsrmon nncnmron. r02. momma cmcunrs.

Be it known t at 1, WILLIAM Bmss, a citizen of the United States, residing at Niagara Falls, in the county of Niagara and State of New York, have invented new and useful Improvements in Variable-Resistance Regulators for Electrlc Circults, of

- which the following is a full, clear, concise,

and exact description, reference being had to the accompanying drawing, forming a part of' this specification.

This invention relates to variable resistance regulators for electric circuits.

The invention is especially applicable to regulation of electric generator field circuits and of lamp circuits as well as being capable of use in many other relations.

One of the objects of the invention is to provide an improved regulator which shall embody to a maximum degree the qualities 'of smoothness of action, sensitiveness, ruggedne'ss and reliability.

Another object is to provide. an improved regulator capable of controlling a heavy current with an even and uniform action and capable of readily dissipating the heat generated.

Figure 1 is a diagrammatic view of the main parts of a regulator constructed in accordance with my invention.

Fig. 2 is a, diagram of a novel system employing the regulator shown in Fig. 1.

The regulator shown in Fig. 1 comprises a variable resistance device 1 controlled by a solenoid 2 through a lever 3. The lever 3 is pivoted at or near its center on a pin 4 and bears on the one end the solenoid plun-' ger 5 and on the opposite end one member of the variable resistance device, namely the conical carbon plunger 6. The variable resistance device comprises a conical carbon contact member 6 and a body of mercury 7 inclosed in a suitable cup 8. The cup 8-is preferably made of iron. The area of contact between the carbon plunger 6 and the mercury 7 may be varied by raising and lowering the plunger which is suspended from the lever 3 by a rod 9. Thecup 8 is closed by a cap member 10 which may be and prefera'bly is made of insulating material. This cap is provided with a guide member 11 which is made of a suitable metal to furnish a guide bearing and for retaining the rod 9 Specification of Letters ratent.

. atented July 22, 1919.

1914. sci-mm. scams.

and the carbon plunger 6 in a central os i t1on and out'of contact with the wal s of the Iron cup 8. The rod 9 is connected to the lever 3 by means of a pin 12 .and an enlarged lu 13 bearing a terminal connectlon 14'. T e rod 9 is insulated from the lever 3 and the rest of the mechanism in any preferred manner. The other terminal may bc connected tothe iron cup which'is in contact with the mercury, as by means of a lug 15 on the side of the vessel or in contact therewlth. A spring 16 is connected at one end to the-lever .3 by a pin 17 and at the other end to a lug 18 attached to the side of the iron cup. The tension on the spring may be ad usted and locked by means of the bolt and nuts 19.

The solenoid 2 comprises a core 5, a wind- 111g 20 and a frame 21. A steadying means for both the solenoid and the contact device may be provided. This is shown as a dash pot at the bottom of the solenoid having a plunger 22 playing in a cup 23 which is mounted in an extension 24 of the solenoid frame. The solenoid core 5 and the plunger 22 are connected by a rod 25. A 'The sha of the carbon plunger 6 is important in determining the characteristic of the resistance device. The smaller the angle of the cone, 2'. 0., the nearer the cone approaches the cylinder the more nearly uniform will be the-variation in resistance for; equal movements of the rod 9. By properly shaping the plunger 6 any desired characteristic can be obtained.

In carbon pile rheostats depending for their action upon variable pressure it is impossible to lower the resistance beyond a certain point except under enormous pres sure. Hence there is a practical limit to the use of carbon pile rheostats where a low resistance is desirable and a fairly Wide range of variation is to be introduced. If heavy currents are to be carried the initial resistance of a carbon pile rheostat causes a very considerable waste of power and a very undesirable heating which is particularly hard to eliminate. In a regulator constructed in accordance with my invention v the resistance may be reduced to practically zero as it is possible to add a metal contact in such a position that when the plunger is.-

at its lowest position the metal contact will the action is even and continuous. "The power of the solenoid need not be very great to operate the rheostat through its.

complete range of action as the device depends not upon compressing any part of the mechanism but merely upon a change of the area of contact. To do thisit is necessary to overcome only the tension of the spring balanced so that vibration or ars will have no eifect upon the regulator. Having no resistance except that of the tension of the s ring 16 to overcome able to cause a very close regulation. It can also be seen that the simplicity and complete balance of the parts renders this regulator capable of withstanding satisfactorily very rough usage. v.

Fig. 2 illustrates a car lighting system employing the regulator above described.

The system comprises a generator having an armature 30 and 9 ing a full charging a field winding 31, an automatic switch 32, a storage battery 33, and lamps 35 connected by the mains 36 and 37 to the generator. A regulator 38 is employed to regulate the voltage of the generator in accordance with'the current output and the regulator 39 is provided in the lamp circuit for regulating the voltage across the lamps 35. When the armature 30 is at a standstill the parts are in the position shown in Fig. 2. As the armature 30, which may be connected to a car axle or the like, begins to rotate with increased speed the voltage of the generator builds up to a value suitable for charging the storage battery 33, the spring 16 of the regulator at this time holding the carbon plunger 6 in the lowest position. When the proper voltage h s been attained the shunt coil 40 of the automatic switch 32 closes the automatic switch to connect the lamps and the battery to the generator. Current then'flows to the battery through over the main 36 through the holding winding 41'of the automatic switch, storage battery 33 and back to the generator over the lead '37. The voltage necessary for causcurrent to flow through the battery is considerably in excess of that required by the lamps 35. The regulator 39 has its variable resistance elements 6-7 connected in the lamp circuit for holding the voltage at a proper value. This is accomplished by a shunt wound solenoid 45 connected in parallel with the lamps. The

'16. The lever 3 maybe statically the solenoid will be the winding 20 of the solenoid core 46 of this solenoid is connected to a car-1 p in circuit with the solenoid winding 20 of theregulator 39. Any tendency toward an increase of voltage across the lamps 35 causes an increase in pressure in the carbon pile 47 and a consequent increase of current through the solenoid winding 20, and this in turn introduces a greater resistance in the circuit of the lamps whereby the voltage across these lamps is held approximately constant. By the verysimple arrangement above described it is possible to charge the battery with full charging current without injuring the lam s 35.

The regulator s own in Fig. 1 is especially adapted to this service as it can properly govern quite a heavy current and in low voltage systems of the class used in car lighting and automobile lighting and starting systems, comparatively high values of current are required in the field windings of the generator. Where a considerable number of lamps are to be supplied with current at a predetermined voltage this type This can be accomplished because all of the parts are of good heat conducting material and are not restricted asto size. Fins or projections may be cast integral with the cup 8 to aid in dissipating the heat.

Although the invention has been described with reference to the particular details of one embodiment, it is not thereby intended to limit the invention in any sense. Numerous changes and modifications, all coming within the spirit of the invention, will suggest themselves to those skilled in the art.

What I claim as new and desire to secure by Letters Patent of the United States is: In a regulator, in combination, vessel containin mercury or the like, a conical electrode uoyed up by said mercury, spring -means biasing said conical electrode to a nesses.

WILLIAM L. BLISS. Witnesses:

WM. A. FRUBAYNE, F. H. Zmmnonrnn. 

